iPhone 6 Wifi, Bluetooth & (GPS?) Signal Weak

Good day!

So I’ve been trying to find some answers here about my device. There are some mixed answers so I want to explain my exact problem hoping that you can help me what needs to be repaired.

My wifi range is quite short particularly the 2.4Ghz. 5Ghz works just fine and has much better range than 2.4. I also noticed that while I was playing some games with some music on the BT speaker, the game (mobile legends) lags and also the bluetooth speaker was cutting sounds at the same time. Is the bluetooth and wifi antenna the same?

Also, at some times, my GPS wasn’t accurately displaying my current location. Now it is.

PS I was like 1-2 feet away from the router and bt speaker. How’s that even possible? Lol